First Actual CPU Energy Use Statistics Published 103
BBCWatcher writes "CNN is reporting that the U.S. Environmental Protection Agency in August asked server manufacturers to develop 'miles per gallon' ratings for their equipment that would provide accurate assessments of energy efficiency. IBM says it is now providing 'typical usage ratings' for its line of z9 mainframe computers, in addition to previously available maximum power ratings. More than 1,000 z9s around the world started reporting (with the owners' permission) on May 11th their actual installed power and cooling demands, so IBM can publish statistics such as how much energy is required to turn on an additional processor to run multiple Linux virtual servers. The answer? About 20 total watts. 'Over time every vendor is going to be asked to provide typical energy use numbers for their equipment. It's what the EPA wants, and this allows us to move beyond simple performance benchmarking to energy benchmarking.'"
Re:Reason To Buy A CPU (Score:2, Informative)
The savings are substantial -- for an average 25,000 square foot data center, clients should be able to achieve 42 percent energy savings. Based on the energy mix in the US, this savings equates to 7,439 tons of carbon emissions saved per year."
http://www-03.ibm.com/press/us/en/pressrelease/21524.wss [ibm.com] (emphasis mine
I think otherwise.
CC.
Re:damn lies (Score:3, Informative)
For example... I was recently shopping for home theater projectors and was doing a lot of comparisons between brands. The two most important things I was looking for were picture quality and brightness. Both have standard metrics such as contrast ratio and lumens. The problem is that the manufacturers know they're being judged on these two numbers, so they just play with the numbers until they get them as high as possible. Sure, you can get theoretically get a picture with the advertised contrast ratio, but the brightness will be terrible. And yes, you can get a picture as bright as advertised, but it will look like crap. The numbers are supposed to give you an indication of the quality of the projector, but instead it's just a dick measuring contest between manufacturers and most would likely sacrifice overall quality just to up their numbers.
I would expect the same will go for CPU manufacturers in this case. Processors will be advertised at XGHz and Ywatts*, but you definitely won't see both X and Y true at the same time.
*Y watts based on our definition of "typical use" while running at a much slower clock speed than X
Yeah but Apple Trounced them (Score:2, Informative)
http://www.mythic-beasts.com/appletvdedicated.html [mythic-beasts.com]
Re:Reason To Buy A CPU (Score:4, Informative)
For a power supply i got a seasonic 330w S12 (variable speed ballbearing fan).
My computer is entirely fanless except for the stock AMD CPU fan and the Seasonic power supply fan. There's not even a case fan. System and CPU temps seem to be stable around 40C.
My vista "index" is 5.0, with the 5.0 being the lowest number and coming from the CPU.
I wanted a really quiet machine. That meant eliminating fans. That meant buying energy efficient parts (the CPU and the Seasonic PS are both spendier than equivalent parts that don't stick to a tighter energy budget). But the machine _is_ quiet. I've got a kill-a-watt at home that I haven't tried out yet but I hope to see less than 100w of consumption. My old socket 754 machine is 5w sleep, ~100w booted but idle.
I'm also going to be consolidating my "always-on" applications (file serving, possibly BT) onto a Windows home server machine so that i can have my other boxes power-save as much as possible without any real service interruption. Having a few songs here, a few videos there, etc means that I can't keep the majority of machines sleeping the majority of the time (WOL is pretty spotty IMO.. if you configure WOL such that a machine "can" wake, it usually will stay awake from other network noise)
One of the other things i bought with this order was a new UPS. Sticking to a smaller power budget has other interesting effects -- like you can get away with a smaller (and cheaper) UPS to get the same amount of uptime.
The marine diesel engine industry (Score:4, Informative)
The International Maritime Organization has created a few different cycles- E2 is Constant Speed Main Propulsion, E3 is Propellor law operated propulsion for example. You pick your cycle, run your engine at a variety of loads, then use weighted averaging on those loads to determine what the emissions would be if the engine ran at E2 all the time. Then you can say that for the E2 cycle, the engine puts out so much NOx.
For computers, someone needs to come up with some different computer cycles. There may be several of them- 50% parallelizable with 25% floating point and 75% integer math, 100% parallelizable with 100% floating point math, etc. Different architectures may take dramatically longer to do floating point or non-parallizable workloads. Only then could you run a bunch of tests and really say that under this load the computer uses this much power to do a certain amount of work in a given amount of time.
This is not new or novel stuff. This is similar to how the EPA tests cars. Some cars do highway miles much better than city miles, so they do both and weight the averages.
Re:Reason To Buy A CPU (Score:4, Informative)
If you don't do any serious gaming, sticking with the onboard graphics will often reduce power draw significantly. If your mobo doesn't have onboard graphics, picking an inexpensive fanless graphics card will draw the least power.
If you were using onboard graphics, I would expect your system would idle around 55w (+-5w or so). Peak power draw would be less than 100w. With the GPU you're using, I'd guess that it adds add 10-20w at idle and another 50w at peak. It'd be interesting to see what the actual numbers are.
Something people often forget is that a good PSU with active power correction will also significantly reduce the apparently load on a UPS (as well as the grid if you don't have a UPS), not to mention that PSUs with APC are normally significantly more efficient. For example, if your system draws 100w but your PSU has a power factor of
These days it's fairly easy to build a system which idles below 50w as long as you're informed. A bit more research will get you something in the 30-35w idle range if not lowre. I do wonder what you had in your old Socket 754 machine which caused it to idle at 100w. I suspect it had an inefficient PSU and a mid-high end graphics card or wasn't using Cool'n'Quiet. All recent AMD systems I've seen which support Cool'n'Quiet idle at 60w or less unless you have a power sucking GPU.